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a recent study of 25 students showed they spent average of $18.53 on gas per week,...

a recent study of 25 students showed they spent average of $18.53 on gas per week, the sample standard deviation of the sample was $3.00, construct a 95% confidence interval for the mean amount spent on gas per week

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Answer #1

Here we need to use t-test as n < 30 and population standard deviation is not given.

For df = 24 and 95% confidence interval t value is 2.06

Confidence interval:

Statcrunch output:

So, the confidence interval is (17.29, 19.77).

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